Some graphics programs, mainly from Adobe, still support the older Adobe Freehand formats, like the FH11 and can open them. As Adobe Illustrator supports both the Freehand formats and JPEG 2000 JPF image format, it is probably your best shot if you are looking for a way how to convert FH11 to JPF.
Convert Adobe FreeHand 11 drawing to JPEG 2000 extended image format (ISO 15444-2).
We found 2 software records in the database related to .fh11 to .jpf file format conversion.
Microsoft Windows software - convert fh11 to jpf on Windows
A powerful vector graphics editor from Adobe
Convert from fh11 file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned fh11 to jpf. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert fh11 to jpf on OS X
Mac version of Adobe's vector graphics editor